With that he ran to the door, to see if there was any fastening on the inside. There was none: in all its long history it never had had one. But a few blows of the right sort, now from the one, now from the other end of his mattock, were as good as any bolt, for they so ruined the lock that no key could ever turn in it again. Those who heard them fancied he was trying to get out, and laughed spitefully. As soon as he had done, he extinguished his candle, and went down to Lina. She had reached the hard rock which formed the floor of the dungeon, and was now clearing away the earth a little wider. Presently she looked up in his face and whined, as much as to say, 'My paws are not hard enough to get any farther.' 'Then get out of my way, Lina,' said Curdie, and mind you keep your eyes shining, for fear I should hit you.' So saying, he heaved his mattock, and assailed with the hammer end of it the spot she had cleared. The rock was very hard, but when it did break it broke in good-sized pieces. Now with hammer, now with pick, he worked till he was weary, then rested, and then set to again. He could not tell how the day went, as he had no light but the lamping of Lina's eyes. The darkness hampered him greatly, for he would not let Lina come close enough to give him all the light she could, lest he should strike her. So he had, every now and then, to feel with his hands to know how he was getting on, and to discover in what direction to strike: the exact spot was a mere imagination. He was getting very tired and hungry, and beginning to lose heart a little, when out of the ground, as if he had struck a spring of it, burst a dull, gleamy, lead-coloured light, and the next moment he heard a hollow splash and echo. A piece of rock had fallen out of the floor, and dropped into water beneath. Already Lina, who had been lying a few yards off all the time he worked, was on her feet and peering through the hole. Curdie got down on his hands and knees, and looked. They were over what seemed a natural cave in the rock, to which apparently the river had access, for, at a great distance below, a faint light was gleaming upon water. If they could but reach it, they might get out; but even if it was deep enough, the height was very dangerous. The first thing, whatever might follow, was to make the hole larger. It was comparatively easy to break away the sides of it, and in the course of another hour he had it large enough to get through.